Any background information described herein is intended to introduce the reader to various aspects of art, which may be related to the present embodiments that are described below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light.
Today, modems, such as cable modems, offer Internet connectivity to subscribers' homes. These modems are typically connected to an information distribution network, such as a coaxial cable network, an optical fiber network, a hybrid fiber/coaxial cable network, or a wireless network, and communicate with a network device outside the home (e.g., a termination system, such as a cable modem termination server (CMTS)). Within the home, the modem may be connected to an in-home network, such as an Ethernet network, an in-home coaxial cable network (e.g., per the Multimedia over Coax Alliance—(MoCA) specification), wireless network, etc., and various devices within the home may use that network to ultimately communicate with network devices outside the home. Additionally, the modem may provide telephone services to the home (e.g., Voice over IP (VoIP) services). Such multi-function modems are commonly referred to as a gateway or gateway device.
The communication protocol used in a cable network between the home device (e.g., cable modem or gateway) and the CMTS is referred to as Data over Cable Service Interface Specification (DOCSIS). The latest protocol that is available today is DOCSIS version 3.1 and, among other changes from earlier versions, expands the possible operating range for upstream communication. Previous versions of DOCSIS used an upstream frequency band from 5 Megahertz (MHz) to 42 MHz. All consumer premises equipment (CPE) devices that are connected to the CMTS in this network, whether set-top boxes (STBs), cable modems, cable modems with integrated voice, routers or Wi-Fi (Gateways) operate using upstream signaling within that frequency range.
However, due to expansion of the network capabilities and a need for higher bandwidth for the upstream communication, DOCSIS 3.1 allows for expanding the upstream frequency range from 5-42 MHz to 5-85 MHz. Future upgrades may expand the range further. However, not all networks may be upgraded at the same time. As a result, the new portion of the expanded upstream frequency range, from 42 MHz to 85 MHz may still be used for downstream communications in some networks. In order to meet these two environments, service providers may deploy two different products using two different input filter circuits or diplexers, one for each environment. Alternatively, the network and service provider may temporarily remove the overlapping downstream communication signals for frequencies below 85 MHz in case they want to deploy a device including a single fixed 5-85 MHz upstream filter. These approaches are not optimal. Therefore, a need exists for a single switchable filter structure that is operable in either one of two network communication configurations and further includes the capability to control the switching of the filter structure.